DEVICE FOR CLEANING AND DEVELOPMENT OF FORMATION Russian patent published in 2016 - IPC E21B37/00 E21B43/25 

FIELD: oil industry.

SUBSTANCE: invention relates to oil and gas industry and can be used for cleaning and development of formation. Device includes tubing string (TS), equipped with filter at bottom, and packer above, installed above formation, seat and swab, installed in TS. Filter is made in form of branch pipe, perforated with holes, which is located opposite formation. In initial state filter holes are blocked with sleeve from inside, which is fixed with stop split spring ring. Sleeve is equipped with external cylindrical groove and internal annular groove is made in TS above filter, in which additional locking split spring ring is placed. Catcher is lowered in TS, which has possibility of fixation on inner surface of sleeve. Sleeve in working position after compression of locking split spring ring has possibility of restricted axial movement upwards together with catcher to fixation of additional locking ring in outer cylindrical groove of sleeve with subsequent release of catcher from sleeve and catcher removing from TS on rope. Sludge-collecting chamber is fixed rigidly to filter from below. TS above inner annular groove is provided with number of channels, closed from inside with seat, fixed by shear element. Plug is installed in TS from wellhead with possibility of axial displacement, which has possibility of tight interaction with seat, destruction of shear element, fixing seat in TS, with opening of number of channels in TS and restricted axial downward movement together with seat till stop of seat against upper end of sleeve.

EFFECT: efficiency of formation development is increased due to preliminary cleaning of bottom-hole area, quality of development is increased due to elimination of reverse penetration of well liquid into formation in wells with high formation pressure and duration of development is reduced.

1 cl, 4 dwg